This invention relates generally to an apparatus and method for packing bulk material in plastic bags, and more particularly to an apparatus and method for packing both variable moisture and high moisture content bulk material such as grain, silage, and the like in plastic bags.
Traditionally, bulk material is fed into a chamber such as a silo structure for packing and storing. Another method of storing bulk material including both variable moisture and high moisture content bulk material comprises packing the bulk material in plastic bags. This not only packs the bulk material more efficiently, but it also reduces costly labor time as well as expensive storage space. The apparatus of the present invention for packing bulk material in plastic bags uses conventional agricultural equipment such as a common farm tractor which has a power take-off, and plastic tubing which has an adequate capacity for storing a predetermined quantity of packed bulk material such as high moisture grain, ensilage or other bulk particulate materials.
The use of impervious bags for storing bulk agricultural products is uncommon. In recent years, however, there has been an increasing trend in agriculture to store agricultural products such as corn, grains, ensilage, and the like, in impervious bags. Such bags replace costly building construction and maintenance and do not require the long term dedication of capital and valuable, productive farmland to a permanent storage structure. These bags of agricultural products are also more easily located in proximity to the area of use because they are not a permanent structure. As a result, it is feasible to change the feeding locations at will.
Horizontally disposed devices are available for packing bulk material which push the bulk material horizontally into bags. German Pat. No. 21 51 116 discloses a horizontally disposed apparatus which has a receiving member, a delivering member, and a horizontally disposed filling device connected to an open end of the delivering member for filling a plastic bag, and a movable platform to support the plastic bag.
While this system, or variations of it, have been used extensively for filling plastic tubing or plastic bags with bulk material, it does have serious drawbacks. One major one is the tendency of the delivering portion to become packed with the bulk material and thereby become plugged. Thus, the delivering end portions require constant attention and adjustment. Another drawback is the resistance of the plastic bag as it fills with the bulk material. As a result, to fill the bags efficiently with the bulk material, the plastic bags require constant attention during the filling operation. These systems presuppose a more or less horizontal arrangement of transferring and resultant problems of maintenance, particularly blocking and stalling. Finally, a great deal of costly energy as well as manual labor are required for its operation.
Bulk agricultural products are difficult both to transfer and to pack because of their variable moisture content, density and viscosity. Devices which have been available for receiving, transferring and packing such bulk material comprising an auger-like member for pushing the bulk material through a housing member disposed in a generally horizontal plane tend to cause the bulk material to pack in the housing member. This blocks efficient passage of the bulk material through the device, and prevents a smooth flow of the bulk material into the plastic tubing for packing. Thus, there is increased spacing between packed segments of the bulk material in the plastic tubing, and this also reduces the storage capacity of the plastic tubing.
Some devices for handling bulk agricultural products are mounted generally horizontally disposed on an elevated platform and and have a delivering portion which extends into the top of a storage container. The bulk material which is transferred through the delivering end of such horizontally disposed devices generally exits as an extruded material compacted by the force of the transferring mechanism. This extruded material is confined within the plastic bag.
Other continuous packaging systems are known which receive bulk material in one chamber, pack the bulk material into a compact mass, and force the compact mass into a tubular packaging material openly disposed over one end of the device for receiving the compact mass.
The use of bags for storage is suggested in U.S. Pat. No. 3,687,061 which discloses a device consisting of a forming mechanism which has two pairs of inclined worms rotatably driven in opposite directions to move the material through the forming channel into a mouth structure which supports a bag. As the material exits the mouth structure, it is pressed against a remote boundary wall anchored to a rope which is attached to a braking drum which regulates the pressing density of the material.
Consequently, a need exists for economical improvements for packing bulk material. Greater reliability and dependability of operation at reduced levels of labor and energy consumption are required for packing bulk materials such as grain, ensilage, and the like in plastic bags.